## Thursday, October 11, 2012

### Bianca's Proportion Post

Proportion Post

Part 1- definitions

• Ratio: A ratio is a comparison of 2 or more quantities with the same unit.
eg. Ratio of girls to boys.

• Rate: A rate is a ratio that compares two quantities with different units.
eg. Rate of laps per minutes.

• Proportion: A proportion is a relationship that says that two ratios or two rates are equal. It can also be written in fraction form.
eg. cookies sold to candies sold.

Part 2- proportion statements

1.) 5 hours to travel 360 kilometers is about 72km/h.

2.) Emma saves 28 cents of every dollar that she earns.  Emma earned \$75 last week.  How much money did Emma save last week? Emma saved \$21 last week.

Part 3- equivalent ratios
• vertically-green
• horizontally-red
• diagonally-blue
equivalent!

Part 4- video

1.) It is not fair.
2.)No.
3.)Because the first guy stole \$3 000 000 000 and only got sentenced for 40 months. While the other guy stole \$100, but he gave it back and surrendered. He still got sentenced in jail for 15 years (180 months). So to get the proportion you have to get the unit rate for the years. You divide the years, so then 40 months is about 3 years. 3 divided by 3 is 1, then divide 3 000 000 000 by 3 and you get 1 000 000 000. So the rate and proportion for the first guy is \$1 000 000 000/year.  So you divide 15 by 15, and whatever you do to one side you have to do to the other. So 100 divided by 15 is 6.66. The proportion and rate for the guy who stole \$100 from the bank is \$6.66/year. It's not fair.
4.) If I was the judge I would've been fair and treated them both equally. I would have also sentenced them in jail for the same amount of time, or maybe even the second guy shorter because he gave the money back.

Bonus

• How tall are the trees? Show your work.
-First I measured the boy on the screen with a ruler. He was about 2cm (the boy looks about 5-6 feet tall). So then I took my finger and measured that it takes approximately 3 boys fit onto one tree (height). So then 2cm=5-6 feet, and if you multiply them both by 3 you'll get 6cm=15-18 feet. So on your computer screen the trees are about 6cm tall. In real life the trees are approximately 15-18 feet tall.

#### 1 comment:

1. Stars: I think I explained the social justice part well, pictures showed my thinking, I also showed good examples.
Wish: Next time I want to try to make my own video.

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